What are people thinking, anyways? There are far better coins with a promising future. BTC, ETH, LTC, and SOL are one of them. I'd advise you choose your coin wisely to see good results in the long run.
They won't listen to you. If they have invested heavily to XRP and other coins that have pumped and then no longer moving at all, the hope is in there and that's what you can't remove to them. Bitcoin is the best choice and we'll never go wrong with it. It's been there for how many years and these altcoins could also stay but we don't know how much it will be their worth in the future.
I bet XRP wouldn't last another decade. You'll see... 
I'll give a trivia to them, many have been at the same rank as XRP for the past several years and now, they're nowhere to be found near to top 100.